# Tk_traffic__signal.py

# Tk_traffic__signal.py

import Tkinter
w, h = 800, 600
canvas = Tkinter.Canvas(width=w, height=h)
canvas.pack()

canvas.create_rectangle(w/2 - 50, 150, w/2 + 50, 450, fill='black' )

while True:
    canvas.create_oval(w/2 - 45, 155, w/2 + 45, 245, fill='red', tag='redLight')
    for i in range(10):
        canvas.create_text(w/2, 200, text=str(9-i), fill='white', tag='red', font='Calibri, 30')
        canvas.update()
        canvas.after(1000)
        canvas.delete('red')
    canvas.delete('redLight')

    canvas.create_oval(w/2 - 45, 345, w/2 + 45, 435, fill='green', tag='greenLight')
    for i in range(10):
        if i < 8:
            canvas.create_text(w/2, 390, text=str(7-i), fill='white', tag='green', font='Calibri, 30')
        else:
            canvas.create_oval(w/2 - 45, 250, w/2 + 45, 340, fill='orange', tag='orangeLight')
            canvas.delete('greenLight')
        canvas.after(1000)
        canvas.update()
        canvas.delete('green')

    canvas.update()
    canvas.after(1000)
    canvas.delete('orangeLight')

Tkinter.mainloop()